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El objetivo de la investigación fue detectar la presencia del ácido desoxirribonucleico (ADN) de Bartonella henselae en muestras de sangre de 100 gatos callejeros de albergues, clínicas veterinarias y casas durante los meses de septiembre a diciembre de 2022 en la ciudad de Guayaquil, Ecuador. Las muestras fueron procesadas en el Instituto Nacional de Investigación en Salud Pública (INSPI). Una vez obtenidas, las muestras se refrigeraron por dos a cuatro horas y luego se trasladaron al laboratorio del ISNPI para su procesamiento. El ADN se purificó y se concentró utilizando el minikit de ADN genómico PureLink y se sometió a congelación para su conservación. La presencia del ADN se detectó en la sangre de los gatos mediante la reacción en cadena de la polimerasa (PCR), lo que reveló que Bartonella henselae estaba circulando en la ciudad de Guayaquil con una prevalencia del 14%.

Cryptic species can present a significant challenge to the application of systematic and biogeographic principles, especially if they are invasive or transmit parasites or pathogens. Detecting cryptic species requires a pluralistic approach in which molecular markers facilitate the detection of coherent taxonomic units that can then be analyzed using various traits (e.g., internal morphology) and crosses. In asexual or self-fertilizing species, the latter criteria are of limited use. We studied a group of cryptic freshwater snails (genusGalba)from the family Lymnaeidae that have invaded almost all continents, reproducing mainly by self-fertilization and transmitting liver flukes to humans and livestock. We aim to clarify the systematics, distribution and phylogenetic relationships of these species with an integrative approach that includes morphology (shell and reproductive anatomy), molecular markers, wide-scale sampling across America, and data retrieved from GenBank (to include Old World samples). Our phylogenetic analysis suggests that the genusGalbaoriginated ca. 22 Myr ago and today comprises six clusters of species. Four of these clusters (G.truncatula,G.cubensis/viator,G.humilisandG.schirazensis) are morphologically cryptic and constitute species or species complexes with wide variation in their genetic diversity, geographic distribution and invasiveness. The other two clusters constitute a single species or a species complex (Galba cousini/meridensis) that demonstrate more geographically restricted distributions and exhibit an alternative morphology more phylogenetically derived than the cryptic one. Further genetic studies are required to clarify the status of bothG. cousini/meridensisandG.cubensis/viator. We emphasize that noGalbaspecies should be identified without molecular markers and that additional sampling is required, especially in North America, Eurasia and Africa to clarify remaining questions in systematics and biogeography. We also discuss several hypotheses that can explain crypsis inGalba, such as convergence and morphological stasis, and hypothesize a role for stabilizing selection in amphibious (rather than strictly freshwater) habitats.

International audience; A molecular tool described here allows in one step for specific discrimination among three cryptic freshwater snail species (genus Galba) involved in fasciolosis transmission, a worldwide infectious disease of humans and livestock. The multiplex PCR approach taken targets for each species a distinctive, known microsatellite locus which is amplified using specific primers designed to generate an amplicon of a distinctive size that can be readily separated from the amplicons of the other two species on an agarose gel. In this way, the three Galba species (G. cubensis, G. schirazensis, and G. truncatula) can be differentiated from one another, including even if DNA from all three were present in the same reaction. The accuracy of this new molecular tool was tested and validated by comparing multiplex PCR results with species identification based on sequences at mitochondrial and nuclear markers. This new method is accurate, inexpensive, simple, rapid, and can be adapted to handle large sample sizes. It will be helpful for monitoring invasion of Galba species and for developing strategies to limit the snail species involved in the emergence or re-emergence of fasciolosis.

HIV infection, acquired with the conscious participation of the recipient, is a complex problem of international concern, especially among men who have sex with men. Behaviors emerge such as bareback (intentionally unprotected anal sex between men) and bugchasing (bareback sex when one participant is HIV+ and the other is not). A group of emerging risk behaviors for HIV infection was characterized. A review of the literature in the MEDLINE, Web of Science and regional SciELO databases was performed. HIV-related search terms such as unprotected sex, barebacking/bareback and bug chasing, were used. Bareback and bug chaser behaviors occur, among other factors, through social homonegativity, ART positive coverage, insufficient prevention campaigns, search for new sensations and attempts to strengthen the relationship with the HIV+ member. Unprotected sex is primarily associated with having HIV/AIDS diagnoses, physical violence due to sexual orientation, viewing homosexual sex sites, and having bought or sold sex. It is necessary to work with individual behaviors that draw individuals close to infection.La infección por VIH, adquirida con participación consciente del receptor, es un problema complejo de alcance mundial, particular entre hombres que tienen sexo con otros hombres. Emergen comportamientos como el Bareback (sexo anal sin protección de modo intencional entre hombres) y, Bugchasing (sexo bareback cuando uno de los participantes es VIH+ y el otro no). Se caracterizó un grupo de conductas emergentes de riesgo hacia la infección por VIH. Se realizó una revisión bibliográfica en las bases de datos Medline, Web of Sciences, y Scielo regional. Se utilizaron términos de búsqueda como, sexo sin protección, Barebacking/Bareback, y Bug chasing, todos relacionados al VIH. Las conductas Barecack, y Bug Chaser se producen entre otros factores por el Homonegativiso social, la cobertura positiva de la Terapia Antirretroviral, campañas de prevención insuficientes, búsqueda de nuevas sensaciones, y el intento de fortalecer la relación con un miembro de la pareja VIH+. El sexo sin protección por su parte se asocia principalmente a tener diagnóstico de VIH/sida, violencia física debido a la orientación sexual, asistir a sitios de sexo Gay y haber comprado o vendido sexo. Se debe trabajar con los comportamientos individuales que acercan al sujeto a la infección.

Chagas disease is a parasitic disease caused by the protozoan parasite Trypanosoma cruzi and about 230,000 persons are estimated to be infected in Ecuador. However, limited studies have been performed in the Amazon region, on the eastern side of the country. We evaluated here the seroprevalence of Trypanosoma cruzi infection in 12 rural villages of the Loreto canton, Orellana Province in schoolchildren aged 5–15 years and in pregnant women. A total of 1,649 blood samples were tested for Trypanosoma cruzi antibodies by enzyme-linked immunosorbent assay and indirect hemaglutination, and discordant samples were tested by indirect immunofluorescence assay. We detected a seroprevalence of anti-Trypanosoma cruzi antibodies of 1.3% in schoolchildren aged 5–15 years, indicating the persistence of a constant and active vectorial transmission in the Loreto County and confirming the need of the implementation of nonconventional vector control. We also observed a seroprevalence of 3.8% in pregnant women, indicating a clear risk of congenital transmission. Further studies should help define this risk more precisely and implement current international guidelines for the diagnosis, treatment, and care of these cases.